The present disclosure relates to a control system, which can be particularly used for a payload such as a camera. The control system includes a pan/tilt head that includes a structure to increase the tilt range of the pan/tilt head.
In the design of any camera control system, an important factor to be considered is the camera's center of gravity (c.g.). A camera control system is designed to control the degree of pan and tilt of the camera. “Pan” refers to horizontal motion of the camera around the vertical axis, i.e. side-to-side motion. “Tilt” refers to vertical motion around a horizontal axis, or in other words rotation in a vertical plane, i.e. up-and-down motion. The further the camera's c.g. is from either motion axis, the more torque is needed to move the camera to the desired location. Historically, designers of remote control pan/tilt camera heads have dealt with the issue of camera c.g. in one of two ways.
In one approach, previous designers chose one or the other (vertical or horizontal) axis and rotated the camera around its c.g. in that axis only. If the designers chose to rotate the camera around the vertical axis, then the camera was mounted on the top of the device. The problem with this design is that as soon as the camera is tilted, the weight of the camera is shifted forward or backward. This weight must then be lifted in order to revert to the original position and, until that is done, the whole system of camera and mount is in an unbalanced state. This imbalance requires more motor force to move the camera. If the designers chose to rotate the camera around the horizontal axis, then the camera was mounted from the side of the device. Here, the camera may be tilted up and down without shifting its weight forward and backward, but additional torque is required to pan the camera since the c.g. of the camera is offset from the center of rotation around the vertical axis.
Other designs feature the camera moving both horizontally and vertically around the camera's c.g. This is done using a relatively large framework and an “L-shaped” or “U-shaped” bracket. The tilting motor and bearings are located to the side of the camera, and the panning motor and bearings are located directly below (or above) the camera. Though the camera usually remains balanced, it is at the expense of a larger and heavier support framework, which must be moved right along with the camera as it is panned. There is thus a need for improved pan/tilt equipment.